Call of Duty: Modern Warfare 3 - Iron Lady

Make your way to the Osprey and wait for the inevitable to happen. But after that, you get to take to the skies. You have three weapons, the 105mm, 40mm, and 25mm. The largest takes the longest to reload but can take out groups of armor with a single shot right down to the 25mm which you can just rake across infantry to clean them up.

During this mission you need to not shoot buildings at first. Later, when you request permission to fire, wait until they say you have permission to fire on buildings with enemy personnel before you fire. Don't shoot the white diamonds and make sure that you watch behind the squad as well as in front.

After you fire on the embassy, you'll be back on the ground. Make your way up the long staircase in front of you. Follow the hallway, taking out enemies on the way. At the end, you'll find a room with a sniper rifle in it. Grab it and use it to take out the machine gunner in the middle of the courtyard. Use this position to clear out the courtyard some and then drop down. Get to the center of the courtyard and defend that position. Once the tank shows up, mark it with smoke and watch it explode. Then jump into the gunship again.

In the gunship, you'll first have to clear a plaza of enemies so that the squad can get some wheels. Once they start moving, switch to the 25mm so you can fend off enemy vehicles. Kill as much as you can to keep them safe. Once they get to the bridge, switch to the 105mm and drop a shell on one of the tanks. You'll jump back on the ground.

Now that you are on the ground, grab the javelin launcher in front of you and use it to take out the two remaining tanks. Move up the bridge using whatever cover you can find. You can still use smoke grenades to mark groups of enemies for air support. When you get to the end of the bridge, you need to hold it for three minutes. Be careful when your chopper finally shows up. It'd be a shame if you got hit by the tail while it was landing and died.